Railway crossing signal



June N, 1940. F. w. GRlswoLD RAILWAY .CQSSING SIGNAL Filed July 9. 19364 Sheets-Sheet 1 June 11`, 1940.

F. W, GRISWOLD RAILWAY CROSSING SIGNAL 4 Sheets-Sheet 2 Filld July 9,1936 Ef i? ufff@ F. w. GRlswoLD- 2,203,988 RAILWAY CROSSING SIGNAL ilodJuly 9, 1956 4 Sheets-Sheet 5 June ll, 1940. F. wl GRlswoLn- RAILWAY(IROSSING SIGNAL mu Juiy 9, 193s 4 Sheets-Sheet 4 JWM??? 202 Frm NKMfr/swap 5f Patented June 11, 1940 UNITED 1 sTATEs i param certesRAILWAY CROSSING SIGNAL Frank W. Griswold, Minneapolis, Minn. AppneatmnJuly 9, 1988,` serial No. 89,748 iolaims. (o1. 177-388) This invention`relates to a signal device and while the device may have various`applications, it is particularly designed for use at railway crossingswhere a `thoroughfare crosses a `railway.` It is desirable at suchcrossings to have an automatic signal which will be turned to stopposition when a train is approaching and which will be turned to nonstopposition when the train has left the vicinity of the crossing.

Itis also desirable and convenient to have such a signal electricallyoperated and to have a minimum of current used, particularly whenthesignal is in non-stop position. It is also desirable to vhave thesignaloperated with simple mech- ]5 anism.

i It is an object of this invention. therefore,` `to provide a signalhaving, simple and eflicient means for moving it to non-stcp positionwhen `there is no train adjacent the crossing and to hold it in suchposition.

It is another objectof the invention to provide a railway signal`adapted for use at rail- 'Waycrossings havinga Signal member `adaptedto `be turned to stop and non-stop positions, said gr, `Signal memberbeing turned to non-stop .position bya plurality of electrmmagnetsacting upon an armature preferably having a winding thereon.

` It is a further object ofthe invention to providea railway signal ofsimple and eiiicient 3de- U :zo sign having electro-magnetic means foroperating it tocause it to assume nonfstop position,`

asirnple and* efficient holding means for hold ing it in saidposition, areleasing means `and gravity-actuated means for operating itto cause gy,it to assume stop position.

These and other `objects andxadvantages of the invention will be fullyset forth in the following description made in connection with the`acco1n-` panying drawings, in which like reference characters refer tosimilar parts 'throughout the several views and in whichj Fig. l. isaview in front elevation of the signal; Fig. 2 is a View in sideelevation of the Signal; Fig. 3` is a partial view `in vertical sectionthrough the casing` and operating mechanism for the Signal;

Fig. l is a horizontalsection taken on line li-Ji.

of 3 as indicated by the arrows; Fig. 5 is a horizontal section taken online 5-5 of Fig. 3 as indicatedby the arrows;

i Fig. 6 is a view in side elevation as seen from the lower side `ofFig. 5; i

t Fig. 'l is a partial horizontal Sectiontaken `sub- 55 stantially online l-wl of Fig. 3 as indicated by Saidlamps facing forwardly andrearwardly rethe arrows, some parts being omitted and others Shown indotted lines;

Fig. 8 is a somewhat diagrammaticview representing in part a horizontalsection takensubstantially on line 8 8 of Fig. 3 as indicated by "i thearrows; and

Fig. 9`is a wiring diagram for the signal. l

Referring to the drawings, a` signal is shown comprising a` base memberI5. This member is shown as a casting having a cylindrical body l0.

with. a bottom flange 5a and opposite flanges lili extending from itstcp downwardlygand out"u wardly to adjacent the edge of flange Ilia.Said base member preferably is formed of two portions and these areconnected by headed and i5.

nutted bolts i extending through bosses ilicon member i5. A Standard orsupport Il is ainbraced` by base member i5 and upstands there` from,said standard having a 'collar Ila resting upon the top of base memberl5. is supported at the top of standard ll, the same having a collar laat its bottom having a plurality of radially extending set screws llitherein engaging standard Il. Standard l is preferably provided at oneside with a door giving acg5 cess to the` interior thereof. Brackets 2liare bolted to the; sides of casing'l by bolts 2l, which brackets extendoutwardly andare formed angle irons extending vertically in parallelrela tion, the same havingupper portions 2da, con- 3o verging to form acentral standard Zlib. Crossed bars.22 are supported at the upper end ofportion 20h, said bars being crossed` at theircentral. portionssubstantially at right angles and having thereon respectively the WordsRailroad `cross- 35 ing. Bracket portions Zc extend vertically from theside portions of brackets 2!! to which are bolted the brackets 29d, thesame extending hori- Zontally to each side of bracket 2B. Lamps 23 aresupported at `the ends of brackets 2M, 40

spectively and havingshields or reflectors 23a at their upper portions.,`Annular plates 23h Surround the forward portions of said lamps and reflectors 23a. The faces of plates 23brare of some 45 dark color andwhilevarious colors may be used, in the embodiment of the inventionillustrated .they are shown as beingiblack. The lenses 23e A casing i32G (ifi and arrestive face portion and a narrow edge of non-arrestiveappearance. While sign 25 might be of various shapes, in the embodimentof the invention illustrated it is shown as of Octagon shape havingsides parallel to the sides of brackets 2U, the corners of said sign atits upper side being substantially parallel to the converging portions20a respectively of brackets 28. While sign 26 might be of variouscolors, it preferably is yellow and the same has the word "Stopextending horizontally across its central portion. The letters of thisword Stop and the letters of the legend Railroad crossing on bars 22preferably have small circular reflecting buttons 26a. A bracket 21 isbolted to one side of signZG, the same having a collar 21a extendingover a boss |812y forming part of and projecting upwardly from the topof the cover |80 for the casing I8. Bracket 21 has a shaft 2lb extendingdownwardly through boss |812` and journaled therein. A 2 Tracks sign 28is placed on the front of casing I8 as shown in Figs. 1 and 2. The shaft27h projecting downwardly from bracket 21 has secured to its lower endan arm 29 having a slot 29a in its lower side substan" tiallyrectangular in cross section. Casing I8 has therein a frame comprisingfour rods 38 extending adjacent the corners thereof, the upper ends ofwhich are threaded in bosses |.8d on the cover |80. A plate 3| formingpart of said frame is supported on rods 3D and has therein a ballbearing 32. A shaft 33 is journaled in bearing 32, the same extendingthrough the central hub of plate 3| and said shaft has a reduced portion33a at its upper end journaled in a block or bracket 34 secured to thecover |80 by screws 34a. An arm 35 is secured to shaft 33 below bearing34 and has a roller 35a mounted thereon disposed in the slot 29a. Shaft33 has secured thereto between bearings 32 and 34, an iron armature 36,having segmental end portions 36a and a reduced. central portion aboutwhich is wound a coil 31. Rollers 31h are mounted on plate 3|, Vadaptedto be engaged by a stop lug 31o on armature 31. Plate 3| has spacedportions 3| a and 3|-b upstanding therefrom at each side secured bybolts 3 |c forming a channel therebetween in which are disposedelectro-magnetic coils 38 of arcuate form. Coils 31 and 38 are energizedat certain times, causing armature 35 to assume the position shown inFig. 4. A pulley or drum 39 having a grooved periphery is secured toshaft 33 immediately below plate 3| to which is secured a hook 40. Avchain 4| has its end link engaging hook 48 and extends around pulley39, said chain extending` downwardly over grooved pulley 42, theperiphery of which is in horizontal alinement with the periphery ofpulley 39. Pulley 42 is journaled on a stud 43 supported in a bracket`44depending from plate 3|, which bracket has a lug 44a acting as a guidefor ychain 4|. Chain 4| has its other end secured to a stud Ma slidablethrough a weight 4|b, said stud having an enlarged lower end forming ashoulder and being surrounded by a compression spring 4|c, one endofwhich engages said shoulder and the other end of which engages the topof a recess 4|d formed in weight 4|b, in which recess studl 4| a isdisposed. Shaft L 33 has secured thereto below pulley 39 an arm 45 41upstandng vfrom a swinging arm 48.` Stud 41 has split keys 49 extendingtherethrough at one side of arm 48 and at one side of bracket 46. A stud`5|) projects downwardly from plate 3| and the same has a small bracket5| secured to one side thereof, which bracket has secured thereto a searor leaf spring 52, one end of which projects freely from bracket 5|.Bracket 46 has an arm extending at an angle thereto somewhat larger thana right angle, the same having an end 46h bent substantially at a rightangle, the end of which is adapted to engage spring 52. Arm 48 ismounted for swinging movement about a stud 53 depending from plate 3|and is held thereon by the split key 54. Arm 48 has adjacent its freeend a block 48a forming an armature adapted toengage and be attracted byan electro-magnet 55 mounted on a bracket 56l secured to a bracket 51 bythe headed and nutted bolts 58, bracket 51 being secured to plate 3|. Acan 6|! issecured to shaft 33 between pulley 39 and arm 45. Said cam hasspaced lugs 69a depending therefrom, through one of which extends a setscrew 6| having a -jamb nut thereon, the end of said set screwprojecting from one side of lug a and engaging one side of arm 45. Theopposite side of said arm has a recess formed therein in which is seateda coiled compression spring |53,` one end of which projects from saidrecess and engages the other lug 60a. Spring 53 is of considerablestrength. With said construction the angular position of arm 45 can bevaried somewhat by manipulation of set Ascrew 6| Cam 68 has a peripheralportion 69h adapted at times to engage a roller 68e mounted on arm 48.Said cam has another peripheral portion 59d which is adapted to engage apin 64 projectingv from a switch member55. v, Cam 6|) vhasv a recess611e between portions 50h and 69d and a pin 65 projects upwardly fromsaid cam adjacent one end of portion 59d. Pin 56 is adapted at times toengage with a surface or shoulder 65a formed on switch member 65. Switchmember 65 is pivotally mounted on anpin 61 depending from plate 3|,thesame being held thereon by a split key 61a. Switch member 65 carries anupper contact member 69 and a lower contact member 10. Switch member 69is radapted to connect switch contacts 1| and 12 carried on insulationblocks 13 and 14' respectively. The contact member 1| is mounted in aholder lla, the same being bent at one end to form a semi-cylindricalsocket in which the enlarged end of member 1| is seated "and swingable.Member 1|a has arms or clips 1lb extending over the sides of member 1|.

A headed pin 15 has its head engaging the a remote side of member 1I@and extends through member 1|, the same having a washer 16 adjacent itsend held thereon in any suitable manner as by a pin extending throughmember 15. A coiled compression spring 11 surrounds pin 1,5betweenwasher 15 and member 1| so that the free end Vof member 1| mayyield somewhat against the tension of spring 11. Contact member 1| isprovided with a binding post 1 |c. Contact member 12 is mounted in aholder 12a having a curved socket portion which one end of member 12 isdisposed. Holder 12a has clips 12b extending over the sides of `member12 and a headed pin 18 has its head engaging the remote side of holder12a and extends through I.

the same and through member 12 the same havin'gr a washer 19 heldthereon in any suitable manner. A coiled compression spring 8|)surrounds pin 18 between washer 19 and member 12 so that the latter isyieldable away from holder 12a against the tension of spring 8H. Contactmember 12 is provided with'a binding post 12e.

l Contact member TU is adapted to connect contact `members 8l andcontact members 82'. These are ers lla, 12d, Sla and 82a haveflatportions en- `is connected to contact member 12.

; of the other electro-magnet winding 38. ductor ID3 extends from oneend of the latter winding `3d to electro-magnet winding '55..` A'conductor IM `extends from winding 55 to con- `gaging the blocks 13 andI4 provided with elongated` slots through which pass the securing screws83. Holder 82a is provided with a binding post 82e. The blocks 13 and T4are secured by screws 84 to a bracket 85 carried on stud 58.

A block 86 is shown in Fig. 3` secured to plate 3l and equipped withbindingposts 8l for ren ceiving the conductors or conducting `currnit tocoil 31.

In Fig. 9 a wiring diagram is shown including a battery or source ofcurrent 53 from the poles lof which conductors 9! and 92 extendrespectively to the rails 53 of the railway track adjacent the signal.Conductors 94 and `95 ex-` tend respectively from conductors 5l `and SZto an electro-magnet coil 95. lCoil 36 is adapted to attract, whenenergized, a swinging armature l 'liand hold it in engagement with a`contact 193 to which extends a conductor 82. Conductor 99 is connectedto a conductor` Hill, which in turn Swinging contact member 55 is shownisalso contact member 1l. A conductor lill extends from conductor "Il toone end of one electro-magnet wind-- ing 38.` A conductor |02 extendsfrom the other end of electro-magnet winding 33 to one end A conductor99. A3conductor` H15-` also extends from `contact 'H to one end ofwinding or coil and another conductor HMS extends from the other end ofthis coil to conductor ID3. The` swinging arm 48 `is shown as is alsothe locking member 45 and arm 45. l

. `Another battery or source of current HH `is shown for thesignalcircuits` proper. A conductor 158 extends from one end or pole ofbatterynlll'l to armature 91. A conductor IBS `extends from conductor[Uli `to contact member 82. adapted to connect contact members 82 andpill. A conductor H extends from one end ofbati tery |01 to lamp 25 anda short conductor, lll

l A conductor HZeXtends trom` conductor Hl! to conductor E33. Aconductor` li3extends-from` v position shown in` Figs. l and 2.

extends .from lamp 25 to kcontact member 8i.

conductor H122` to an oscillating flasher contact H4. `Contact H4isadapted alternately toen` gageccontacts H5. A conductor `H5 extendsfrom one contact H5 to one lamp 2.5 `andra `con-- ductorlll extends fromthe other sideof this lamp to contactymember Btl `through conductor lHI. A conductor HB extends `from the other. l contact l l5 to theotherlampfi anda conductor Hextends from this latter 'lamp `to conductorIn` operation when no train is in thevicinity of the crossing the signalwill `be disposed with the edge of plate .25 directed toward the highwayso that `said plate will be at right angles to' the extendssubstantially parallel to the highway` and the face thereof is notvisible to trahie approaching the railway crossing. At thisltime theelectrol magnet 95 shown inrFig. 9 is energized an-d armature 91 is heldagainst Contact 9B. Electro-mag- Swinging contact member is `shown iPlate 251 then holding armature 48a thereagainst. The weight 4 lb isacting by gravity to pull on chain 4|, tending to rotate shaft 33 andturn the signal to stop position or the position shown in Figs. 1 and 2.Since the effort exerted by arm 451s directed at oneside` of the pivot53 of arm 48, the weight is exerting a turning movement on `arm 48 butat l avery disadvantageousangle. Said arm cannot turn because magnet isholding armature 48a.

Shaft 33 cannot turn'because arm 45 is engaging arm 45a. The signalisthus locked in non-stop position and as` stated is under stress ofweight 4|b to move to stop position. Magnet 55 takes very little currentasY it has ahigh resistance winding. When a train approaches thecrossing, rails 93 are connected by the locomotive and cars and battery95 is short circuited. Suiiicient cur` rent does not then flow to magnet`96` to hold armature 9T and it drops down against the stop 81a. rl'hisopens the circuit through magnet 55 so that armature 48a is no longerheld. The

stress on shaft33 and arm 45 now swings arm 48 in. a clockwise directionabout its pivot 53. it thus swings the terminal 45h of arm 'it` is movedagainst spring 52 and member 4B is swung in `a counter-clockwisedirection about its pivot 4l. Arm 45a, is swung away fromshoulder 45a,`as

shown in dotted lines in Fig. 8, so that arm 45 is Ii. released. Theweight lib which is quite heavy now turnsshaft 33 and arm 35 acts on arm25` `through roller 35a to swing sign 25 ninety de grecs to the stopposition shown in Figs. l and 2.

The face of sign 26 now faces the highway and trahie is warned that atrain is approaching.

shaft 33 revolves in a counter-clockwise direction,`

peripheral portion 65h of cam 5l] soon engages roller e and arm 48 isheld in position with armature Maadjacent magnet 55. turns, one side ofrecess 60e enga-ges pin 54 and this swings switch member in a clockwisedirectionabout its pivot 61 and contact member AS JI'.

As cam 5i) 69 connects contact members Tl and l2. Peripheral portion 65dengages pin 54 andholds switch member 35 in connecting position asshownin Fig. 8. When contactlmembers lll and 'l2 are connected, part `of acircuit is completed through the coils 3'! and 38, this circuitextending through conductors 99, lllll, Contact members l2,

55 and 'H and through conductors Uil, H15, lili, IBB, H33 and H2 tobattery 57. However,

the'circuit is open at contacte and armature Si. i

When the signal is in stop position Contact mem" `loer 'lll is alsoswung with contact member 55,

the same being connectedvand contact members 5l `and 32 are connected. Acircuit is now closed through lamp 725 which, referring to Fig. 9, can

be `traced from battery HH, Vthrough conductor H18, conductors |06,contact members 37?., 7b and y 8l, conductor Hl, lamp 25 and conductorH0 to battery I0?. Lamps 23 are `alternately illuminated andextinguished by operation of flasher mem-y ber `H4. The circuits forthese` lamps `can be traced from battery 101, conductor H0, conv ductorH2y conductor H 3, member H4, contact H5, conductor H6, lamp v23,conductor Il?, conductor HI, contact members 8l, "EB and 82, conductor|09 and conductor iilto `battery it?. The circuit for the other lightwill pass through from flasher member H4, contact H5, conductor i i8,lamp 23 and conductor H9 to conductor Ill and thence to battery |01 asalready described.

The signal is thus in stop position with lamps 23 flashing and the barsor sign 22 illuminated; A very conspicuous warning isthus given traliicon the highway to stop.

When the train leaves the vicinity of the crossing the short circuitcaused by connection of `rails 93 is removed and current again ows tomagnet S6 and armature Slis attracted. A clrcuit is now closed throughthe windings 38 and 3l and armature 36 which, while the signal was instop position, had its segmental portions 36a. at 90 degrees from theshowing in Fig. 4 or between the ends of coils 38, is now attracted andquickly moved to the position shown in Fig. 4. This turns shaft 33 in aclockwise dlirection as shown in Figs. -5 and 8, `pulley 39 is turnedand chain M is wound up on pulley 39 moving over` pulley t2 and weightMb is again raised. As cam (il) swings with shaft 33, pin 66 engages theside or surface 85a of switchmember 65 and said member is swung in acounter-,clockwise direction about its pivot 61 so that contact members69 and "iii are swung to disconnect contact members 'Il and 12 andcontact members 6I and 82. When this occurs the circuit through themagnet coils38 and through the armature coil 31 is broken and Aarmature33 remains in the position shown in Fig. 4. When armature 9'! wasyattracted it engaged contact memberf98 and the circuit was again closedthrough magnet 55 and the latter energized. Armature y43a is again heldand arm @5 moves into positionto engage the end of arm 86a. The signalhas now again been moved to non-stop position.` When contact lmem-ber'i8 was swung to disconnect contact members 8| and 82, lamps 23 and 25were extinguished and the Signal was no longer illuminated. When thedescent of weight Md is stopped by lug 3'lc engaging the stop 31h' onplate 3i spring Mc cushions the shock. Lug 31e engages the other stop31h to stop armature 36 when the signal is moved tonon-stop position.

Froin the above description it is seen that applicant has provided avery simple and very efflcient structure of railway signal. The magnetcoils 38 exert great force onarmature 331 and act quickly to turn shaft33 and place the signal in non-stop position after the train has leftthe vicinity of the crossings. While the signal is being held innon-stop position very little current is used. When the signal plate orsign 26 is in its two positions arms 35 and 29 are disposedsubstantially at right angles so that the signal cannot be turned byforce applied to sign plate 25. The use oi the magnet coils 38 andarmature 3S eliminates the necessity for a regular electrical motor andthe necessity for reduction gearing between shaft 33 and such a motor. Avery compact structure is thus produced and one that operates with greatcertainty and precision. The

signal has been amply demonstrated in actual practice and found to bevery successful and efficient.

It will, of course, bev understood that various changes may be made inthe form, details, arrangement and proportions of the parts, withoutdeparting from the scope of applicants inven* tion,wh'ch generallystated, consists in a device capable of carrying out the objects aboveset forth in the parts and combinations of parts disclosed and dened inthe appended claims.

What isv claimed is? 1.v A railway signal having in combination, asignal member adapted to be turned to stop and non-stop positions, meansfor moving said signal to non-stop position including a shaft, a membercarried by saidl shaft, a swinging arm having a locking means forengaging said member to hold said shaft in position when said signal isin non-stop position, an electro-magnet for holding said arm in positionwith said means engaged, said arm carrying an armature for saidelectromagnet, said shaft being disposed to swing said arm away fromsaid electro-magnet at a disadvantageous leverage so that when saidarmature is engaged with said electro-magnet said arm will be easilyheld thereby 'and means on said shaft for moving and holding said armadjacent said `electro-magnet when said signal moves to stop position.

2. A railway signal having in combination, a signal member adapted to beturned to stop and non-stop positions, means for moving said signal tonon-stop position including a shaft, a second member carried by saidshaft and rotatable therewith, an electro-magnet, an arm pivotedadjacent one end to swing about an axis spaced from said shaft, said armhaving an armature adjacent its other end adapted to engage saidelectro-magnet, a locking means carried by said arm comprising an anglearm pivoted thereto, one end of whichengages said second member toholdsaid signal in non-stop position, a third member engaged by the otherend of said angle arm to swing the same upon movement of said swingingarm and release said second member for permitting it to swing past saidarm and to permit said signal member to be moved to stop position.

3. A railway signal member having in combination', a casing, a signalmember mounted above said casing for movement to stop and non-stopIpositions, means for moving said signal to nonstop position including ashaft, a locking arm secured to said shaft, means for varying the an-`gular position of said arm, a swinging arm pivoted to swing about anlaxis spaced laterally from said shaft, an armaturecarried by saidswinging arm, an electro-magnet engaged by said armature, a lockingmember of angular form swing# ingly mounted on said swinging armadjacent the pivoted end of the same one end of said member ybeingadapted to engage said locking arm to hold said signal in non-stopposition, a member engaged by the other `end of said locking member andadapted to move the same to release said locking arm upon movement ofsaid swinging arm away from said electro-magnet and means for energizingsaid electro-magnet when said signal member is in non-stop position andIdeenergizing the same when said signal member is to move to stopposition.

4. A railway signal having in combination, a signal member adapted tojbeturned to stop and non-stop positions, means for moving said signal tonon-stop position including a shaft, a member `carried by said shaft, anelectro-magnet, an arm pivoted adjacent one end to swing about an axisspaced from saidshaft, said arm having an armature adjacent its otherend adapted to engage said electro-magnet, a movable locking meanscarried by said arm adapted toengage said member when said signal is innon-stop position with said armature engaging said electro-magnet, saidshaft andmember :being disposed to swing said arm away from saidelectro-magnet at a disadvantageous leverage so that when said armatureisV engaged with said electro-magnet saidarm will be` easily heldthereby, a cam on said shaftv engaging said arm shortly after saidlocking means is released upon said signal member moving `to stopposition to move and maintain said armature close to saidelectro-magnet.

, 5. A railway signal device having in combination, a casing having aplate-like top cover portion, a plate 4supported within said casing andspaced below said cover portion, a magnet coil bracket upstanding fromsaid plate, a` pair of `electric magnet coils on said bracket, saidcoils being spaced from each other, a vertical shaft jiiuri'laled` insaid plate `and in said cover portiona signal member mounted above saidcasing` and operatively connected to said shaft so as to oscillate inunisonwith it, an armature carried` f centrally on said shaft above saidplate and disposed between said coils, so that,iwhen energized saidsignal will be moved to non-stop position, means supported from thelower side of said plate for holding said signal in non-stop positionafter i said coils are de-energized, and means secured to said shafttending to turn the same to move said signal to stop position so thatsaid signal will.

move to stop position when said holding means becomes inoperative. l

6.` A railwaylsignal device having in 'combinaption, a casing having aplate-like top cover p0rtion, a plate supported within said casing andspaced below said cover portion, a magnet coil bracket upstanding fromsaid plate, a pair of electric magnet coils on said bracket, said coilsn being spaced from each other, a Vertical' shaft` `journaled in saidplate and in said cover portion,

a signal member mounted above said casing and operatively connectedtosaid shaft so as to oscil-` late in unison with it, an armature carriedcentrally on said shaft above said plate and disposed between saidcoils, so that, when energized said 1 signal will be moved to non-stopposition, means supported from the lower side of said plate for holdingsaid signal in non-stop position after said coils are de-energized, saidshaft extending through said plate and means secured to said shaftadjacent the lower side of said plate tending to turn said shaft to movesaid signal 'to stop position so that said signal will move to stop`position when said holding means becomes inoperative.

l 7.`A railway signal device having in combination, a casing having aplate-like top cover portion, a plate supported withinv said casing andspaced ybelowfsaid cover portion, a magnet coil bracket upstanding fromsaid plate, a pair'of electric magnet coils on said` bracket, said coilsbeing spaced from each other, a vertical shaft journaled in said: plateand in said cover portion, a signal member mounted above said casing andoperatively connected to said shaft so as to oscillate in unison withit, an armature carried centrally on said shaft above said plate anddisposed between said coils, so that, when energized `coils aredeenergized whereby said signal will move to stop positionwhen said lastmentioned means becomes inoperative. i

FRANK W. GRISWOLD.

